Builder

So hopefully last kick at this. I'm still hoping to use the inner wheels, if we can get the shims. I found a source, see my last post, but I'm not going to buy 2400 of these things even if they are 0.1 cent each. Hopefully this is an item that the store could stock, and use to get the mini wheels to an even 9mm wide so they could be matched with the regular wheels just by adding an extra 1mm shim. How about it, Mark?

This iteration:
1. puts the fixed wheels back on top
2. adds some brackets to bolt the legs to the c-beams for more strength
3. adds bracing for the bed and bolts to hold down the spoiler board, makes the spoiler board and bottom frame one solid assembly
4. shortened up the motor standoffs from 40mm to 30 mm
5. cleaned up everything, added all the missing bolts

****, this thing uses over 150 8mm bolts and t-nuts , and that's not counting the wheels, the c-beam actuators, or the motors. Hope the store has quantity pricing.

Staff MemberResident BuilderBuilder

I'll check them out, who knows what can be added to our OpenBuilds inventory.

And talking about precision, I started to draw some parts with high detail, so when some one is doing a precise SketchUp drawing they won't get any surprises when they get the parts in. This is the 24v PSU we are shipping now, it's just the body and tomorrow I'll have the cover and PCB drawn as well. I'll have to look into a good fan drawing, not going to do that one from scratch although if there isn't an option, I will do it myself.

Staff MemberResident BuilderBuilder

Soooo.... I was updating info on the Mexican OpenBuilds site. ¿Guess what?

The bearings of the mini V wheel are 105zz, thus 4mm wide and not 4.2mm as stated in the specs from the shop. This means that the mini wheel is 9mm wide and not 9.4mm, so, to line the mini wheel up with a full size V wheel you can just add an extra shim of 1mm on top of the spacer. I checked the mini wheel and it was about 9mm (8.97mm, close enough). No need for special shims although I was thinking of a brass shim with an ID of 8mm, outside 12 to 15mm would be nice, but that's another story .

Builder

@Metalguru
I like this design a lot. I am interested in doing some wood projects that would require more Z axis than some of the other machines would allow. Would it be possible to get the skp of your gantry plates?

Builder

Sure, I can do that. The design has evolved a bit since the drawings above. I have added and changed a few of the stiffener plates. I also modified the gantry plates a bit by moving the inner V wheels out to the edges of the plate both for better rigidity and to allow you to adjust the offset spacers more easily. I also added pockets for all the bolt heads so they are recessed into the gantry plate below the surface to eliminate the need for washers and spacers. In addition, all four of the gantry plates are identical to make life easier, and the X and Z plates simply bolt back to back so you can remove the Z gantry complete assembly by taking out a few bolts. Note that the smaller holes on the outside periphery of the gantry plates are meant to be threaded M5. These holes are 4.2mm diameter instead of 5mm.

This build requires some pretty specific order of assembly, since it's difficult to get some of the parts aligned properly. Hence some of the changes in brackets, wheel position, etc. By the way, you can change the size of the build just by using larger C-Beam actuators, and changing the length of a few v-slot pieces on the base. I have designed models with 750 x 750mm and 1000 x 1000mm C-Beam actuators. Or, you can mix and match, i.e. 500 x 750, or 750 x 1000mm, or even 500 x 1000mm.

I was going to just drop the whole Sketchup model in so you can look at it from all angles, but it's about 25megs. And, I'm not sure you can download it from here. let me know if you want the whole model or just the plates and how I can best get them to you.

Note that I was somewhat of a Sketchup beginner when I did some of this stuff so the model may be less than ideal in a few spots. I would carefully check all dimensions against known good parts before committing to build the gantry plates. There may be some stuff like tee nuts missing, etc, but you get the idea.

Staff MemberModeratorResident BuilderBuilder

Metalguru, not sure why the file is that large based on what you have shown but you may have a bunch of unnecessary artifacts hanging out in the file. They are fairly easy to get rid of if you have a problem with the file size.

Builder

Thanks Rick, let me give that a try. As I said, I was a beginner Sketchup user when I started this, and probably got way too many components and crap in the file. Let me try your suggestions right now.